David Cameron's barrister brother has had a serious fraud trial stopped because of the cuts the Government has made to legal aid.

The significant ruling could pave the way for others accused of crimes to get their cases thrown out, it has been warned.

Alexander Cameron, QC, representing five of those accused for free, argued the fees cut meant not enough competent barristers could be found to represent the defendants.

He blamed it squarely on the cuts and said there was no way the men could get a fair trial.

Judge Anthony Leonard QC agreed and stopped the trial, which would have been the first case brought to court by the new Financial Conduct Authority.

He said simply adjourning the matter would just clog up the courts and he did not think the defendants would be able to find representation.

Following the ruling when asked if he was embarrassed about the case, the Prime Minister said: "My brother has made arguments on behalf of his clients in court and the judge has made a decision.

Barristers staged a walkout over cuts in March

"That's the process, that's the way it should be."

Barristers had cautioned the legal aid cuts, the state funding which covers barristers' fees, would bring about the collapse of the British justice system.

Philip Smith, a partner at the solicitor firm Tuckers which represents one of the defendants, Dale Walker, said the ruling paved the way for other people facing criminal trial to have their case thrown out if they are not properly represented.

Speaking outside court, he said: "I have been a solicitor for 21 years and this is unprecedented.

"It is a very brave decision by the judge, but it is a just decision."

He said he knew of eight other complex cases where defendants had failed to find barristers.

Lee Adams, a partner at Hughmans solicitors who represents another defendant, said: "This is an unprecedented decision, it is enormous.

"This is absolutely the right decision because it is preventing a situation where innocent men may have been convicted for lack of proper representation.

"I think justice secretary Chris Grayling needs to think about his position very carefully, otherwise he risks the effective collapse of the most serious cases."

The Government has said barristers refused to work on the high-profile case to make their point on the cuts to legal aid.

A Ministry of Justice spokesperson said: "Barristers have refused to work on this case - and a number of other Very High Cost Court Cases - because they do not agree with savings the Government is making to legal aid."

They said if a QC accepted the case they could have received around £100,000 for working on it and that the Government had made sure the Public Defender Service had a number of suitably qualified advocates available to act.

The Government has cut legal aid fees by 30% in complex, high-cost cases and 6% in other crown court work in an attempt to shave £220m off the annual £2bn legal aid bill.